The present invention relates generally to crater fill controls for a welding-type process and, more particularly, to a method and system of adaptively activating an automatic crater fill feature of a welding-type system based on the type of welding-type operation being carried out. The present invention is particularly applicable with automatically delineating between a tacking mode of operation and a welding mode of operation.
Tacking is a welding technique that is commonly used in light industrial applications for preliminarily fusing workpieces to one another such that the workpieces can be handled in a more manageable fashion when a final, complete weld is used to complete the fusing process. A “tack” is generally recognized as a light non-permanent weld between workpieces that can, if needed, be broken without damage to the workpieces. Tacking is often used in applications where a relatively precise alignment or orientation between workpieces to be joined is needed. Tacking allows the workpieces to be lightly weld together in a manner that allows the “tack” to be broken if the desired alignment is not achieved and retacked. Conventional welding techniques, such as Gas Metal Arc Welding (GMAW), which is also referred to as Metal Inert Gas (MIG) welding, and Gas Tungsten Arc Welding (GTAW), which is also referred to as Tungsten Inert Gas (TIG) welding, are then used to fuse the workpieces together with a conventional weld. Tacking of workpieces is generally achieved by running a very high energy, low voltage current between the workpieces. Dedicated tacking machines may be used for tacking or conventional welding machines may also be used.
A drawback of carrying out tacking with a conventional welding machine is crater fill controls. Many welding systems have crater fill features that can be activated such that the power source gradually ramps down at the completion of a weld event. Through this gradual ramping down, additional metal filler is delivered to the weld and is used to fill the divot or crater that typically occurs in a weld upon termination of the weld event. Generally, it is preferred to utilize a crater fill process such that the weld is cosmetically consistent, but crater filling can also be advantageously used to maintain structural consistency and integrity of the weld. Absent the filler material, the end of the weld may prematurely fracture thereby causing damage to the weld and affect the integrity of the fusion.
During tacking, however, there is less concern regarding the strength or cosmetic appearance of a tack. Additionally, tacking is generally carried out in a relatively quick manner; however, crater filling adds time to the welding process. Moreover, tacking is a technique used to form a non-permanent bond between workpieces such that the bond can be broken and the workpieces separated from one another damage free, if desired. Crater filling, however, adds to the amount of bonding metal between the workpieces which may hinder the separating of workpieces.
Some welding systems have been developed that allow a user to selectively enable or disable the automatic crater fill capabilities thereof. Some systems are set to a crater fill control OFF default. As such, for a user to take advantage of the crater fill capabilities of the welding system, the user must remember to enable the appropriate features when establishing the operating parameters of a welding session. Other systems are set to a crater fill control ON default. With these systems, the user must remember to disable the crater fill control features when tacking to avoid the time-consuming delivery of additional filler material to the weld.
Requiring a user to manually activate or deactivate a crater fill control feature of a welding system can be particularly problematic. For instance, if a user deactivates the crater fill control feature, tacks workpieces together, the user must then return to the control panel of the welding system, manually activate the crater fill control feature, and then return to the tacked workpieces and conventionally weld the workpieces together. For the user to then carry out another tacking process, the user must re-deactivate the crater fill control feature and iteratively repeat the tacking and welding processes. This can be particularly time consuming if the tacking and welding is carried out relatively remotely from the welding system which is not uncommon in industrial applications.
One solution is to have a dedicated tacking machine and a dedicated welding machine. As such, the user can use the tacking machine to tack the workpieces and then use the welding machine to complete the welding process. Such a solution, however, can be particularly costly as it requires additional equipment and, moreover, an inefficient use of resources for those welding machines capable of operating at the high energy, low voltage current levels required for effective tacking.
It would, therefore, be desirable to have a system and method capable of automatically determining if a tacking or a welding operation is being carried out and automatically setting operating parameters of a welding-type system accordingly.